Front end options 76/77 aircooled

[brg1200]

Hi fellas.
I have a really ratty, part cafe'd RD400. To say it's a mongrel wouldn't do it justice.
Forks stanchions are pitted beyond affordable redemption and the brakes are FUBAR.

Have an option to acquire a Variable Damper (1986) front end complete, was thinking this might be an easy graft, apart from the brakes.

A couple of questions, if anyone knows:
I'd like to keep the original wheels, or at least the style, what Yams had a twin disc with the straight spokes?
Is the single disc front wheel practically convertible to twin discs? Unlike the later LC's they've skimped on the metal on the non-disc side, would need building up or some kind of additional part to make a disc mount.

This bike will never be an "original" minter, it's a 76 points motor in a 77 frame, everything is butchered and jungle engineered - truly horrific, but it has potential.


Regards from South Australia.

[brg1200]

Just for noting, I have considered just running one caliper, it can't be worse than what it had originally, but I like the 'balance' of twin discs.
I reckon the XS 500 of the same era had twin discs, but they're practically extinct. Any other peeiod models with mags and twin discs?
Also, being in South Australia, this really is the far end of the supply chain.

[sispeed]

Hi,
did I read correct that you are putting an RZ YPVS frontend in?
If so you have to stick the fork legs through your upper triple, because they are longer.
If you want to use the Spoked wheels of an RD you need different bearings or inserts the front axle diameter is 15 vs. 17 if I remember correct.
Regards Siggi

[ianr4863]

Have a look at XS650 wheels . I dont know what years they changed them but they had single and twin disc set ups on wire wheels then cast wheels .

[Ozhammer]

XS 750's & 850's also ran twin disks.

Rgds
Ozhammer

[brg1200]

Thanks guys, I'll look those ideas up, make some notes.
A few names/handles on this forum seem familiar, I guess I'm not surprised! :-)
Right, finished work, better get home and get the spindles out to compare

[guiri]

hi, the Yamaha SR250 had a 18 inch front wheel for a few years and single front disc, wheel spindle is same diameter as ypvs forks so easy fit. i have a full ypvs front end in my rd250e race bike,drops straight in.

[brg1200]

Thanks Guiri

[brg1200]

Well I found a bare 18" front wheel with drillings for discs both sides, no idea what it's off though!

[guiri]

Mar 30, 2017 6:49:21 GMT 1 brg1200 said:

Well I found a bare 18" front wheel with drillings for discs both sides, no idea what it's off though!

if tis yamaha maybe its a xs wheel. many parts were similar to rd in that era.


john.

PS.. what part of aus you in. my uncle pat lives in brisbane.. still never got round to..nipping over ..lol.

[brg1200]

Ho ho, you should go visit!
I'm in Adelaide, South Australia.

[4l04ever]

If you want to fit YPVS forks, look at the 31K/29L model forks, as they are shorter than the F1/F2/N1/N2 type. They are all 35mm, so will fit straight into 250/400E/F yokes.

[brg1200]

Yes, I'm thinking 31k type forks as they're simply much more available here. Hardly any aren't "waisted" near the top though, so limited options for sliding them up and down through yokes to alter geometry.